Lists all RAS tag identifiers.
Values:
| IGMDTAG_ID_RAS_FORMAT | RAS metadata format identifier. |
| IGMDTAG_ID_RAS_MAGIC | RAS magic value. |
| IGMDTAG_ID_RAS_WIDTH | Image width. |
| IGMDTAG_ID_RAS_HEIGHT | Image height. |
| IGMDTAG_ID_RAS_DEPTH | Image depth. |
| IGMDTAG_ID_RAS_LENGTH | Length of the image data (which is the length of the file minus the length of the header and colormap). |
| IGMDTAG_ID_RAS_TYPE | RAS format type. |
| IGMDTAG_ID_RAS_COLOR_MAP_TYPE | Color map type. |
| IGMDTAG_ID_RAS_COLOR_MAP_LENGTH | Color map length. |